Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations mark this as a non-read, open-world mutation, and the description meaningfully extends that: cancellation is irreversible, it removes the appointment from the calendar, and with notify_client it emails and texts the client ('reaches other people'). That external-notification and irreversibility detail is exactly the behavioral context annotations do not carry.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose and scope are front-loaded and most sentences carry distinct information (irreversibility, notification, confirmation, auth). The second sentence partially restates the first ('Cancels the appointment and removes it from your calendar'), which is mild redundancy but not enough to hurt usability.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 3-param mutation tool with full schema coverage, annotations, and no output schema, the description covers everything an agent needs: scope semantics, notification behavior, irreversibility, auth requirement, and confirmation expectations.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds meaning beyond the schema by explaining what whole_series does (cancels the entire repeating series) and what notify_client actually triggers (email and text to the client), which the schema only labels generically.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a precise verb+resource (Cancel one appointment) plus a conditional scope (this and all future appointments if it repeats), which cleanly separates it from siblings like glossgenius_reschedule_appointment and glossgenius_book_appointment. An agent can route to or away from this tool without opening the schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear context: cancel cannot be undone, and to re-create the booking use book_appointment. It also states the confirmation default and the API-key/access prerequisite. It stops short of explicitly listing when NOT to cancel (e.g. reschedule as an alternative), so it is strong but not exhaustive.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.